%% You should probably cite rfc4154 instead of this I-D.
@techreport{ietf-trade-voucher-vtsapi-06,
    number =    {draft-ietf-trade-voucher-vtsapi-06},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-ietf-trade-voucher-vtsapi/06/},
    author =    {Masayuki Terada and Ko Fujimura},
    title =     {{Voucher Trading System Application Programming Interface (VTS-API)}},
    pagetotal = 32,
    year =      2004,
    month =     feb,
    day =       17,
    abstract =  {This document specifies the Voucher Trading System Application Programming Interface (VTS-API). The VTS-API allows a wallet or other application to issue, transfer, and redeem vouchers in a uniform manner independent of the VTS implementation. The VTS is a system for securely transferring vouchers; e.g., coupons, tickets, loyalty points, and gift certificates. This process is often necessary in the course of payment and/or delivery transactions. This memo provides information for the Internet community.},
}